Tvheadend

Hi All,

I have a strange issue occurring when recording an HD channel and watching another HD channel. I am able to reproduce this every time by initiating a recording of an HD channel then switching to another HD channel, then after approximately 5 minutes the channel I am watching stalls and I see the following in the log file:

Jan  6 20:20:25 tvheadend tvheadend[1045]: parser: transport stream H264, DTS discontinuity. DTS = 16059600, last = 10922400
Jan  6 20:20:25 tvheadend tvheadend[1045]: parser: transport stream AC3, DTS discontinuity. DTS = 15926211, last = 10825731
Jan  6 20:20:25 tvheadend tvheadend[1045]: parser: transport stream MPEG2AUDIO, DTS discontinuity. DTS = 15936689, last = 10826129

If I leave the channel I am watching it will then eventually come back to life just after the above message appears. The stall lasts for around a minute, then the above message is logged and then the channel plays properly again.

I tried changing the recording format from MKV to TS but the symptoms are the same.

I then has a look at how much memory tvheadend is using and I was amazed to see that it had a 2.5GB VSZ registered in ps output, see below:

# ps -e -opid,ppid,rss,vsz,comm,args | grep tvhead | grep -v grep
 1045     1 580380 2428540 tvheadend     tvheadend -f -u hts -g video

I then restarted tvheadend and on restart the process immediately allocated 1.5GB memory to itself:

# service tvheadend restart
tvheadend stop/waiting
tvheadend start/running, process 2635

# ps -e -opid,ppid,rss,vsz,comm,args | grep tvhead | grep -v grep
 2635     1 55624 495916 tvheadend       tvheadend -f -u hts -g video

# ps -e -opid,ppid,rss,vsz,comm,args | grep tvhead | grep -v grep
 2635     1 133584 1558984 tvheadend     tvheadend -f -u hts -g video

The above is tested on an Ubuntu 12.04 LTS server ESX virtual machine, but the issue is reproduceable on a bare metal system running Ubuntu 12.04 LTS server with 8GB memory (I cannot test with the 8GB system anymore).

I installed tvheadend using the Adam Sutton PPA listed on the download page. The version is:

HTS Tvheadend 3.2.34~gfaee94b~precise

The system is configured with the following DVB-T/DVB-S2 tuners:

Hauppauge WinTV Nova-T-500
Digital Devices GmbH Octopus LE DVB adapter (Cine S2)

I am using OpenELEC 3 RC1 as the client to watch the channels with using the TVHeadend PVR client add-on. All systems are connected via 1Gb network.

I've read a couple threads in the forums relating to memory issues and seen a couple bug reports but it looks like they were fixed. I'm wondering if I have stumbled upon a new one or if this is normal for TVHE to pre-allocate this much memory

Any thoughts would be appreciated.

Thanks